[Asymmetrical bilateral optic neuropathy. Case report].

BACKGROUND Diagnosis of traumatic optic neuropathy is difficult during primary care as a result of the absence of optic disk changes or coexisting injuries that may be more apparent. Although there are functional signs that suggest its presence, the lack of a comparison parameter may further prevent its detection. A case of bilateral traumatic optic neuropathy is analyzed to emphasize the need for functional evaluation in the injured eye. CLINICAL CASE A 34-year-old male presented with severe head trauma, loss of consciousness and type III Lefort facial fracture as a result of a vehicular accident. Seventy two hours after the accident, the left eye had only light perception and an afferent pupillary defect. The right eye had visual deficiency not explained by anterior segment injuries. Therapy was aimed at the left eye and, during follow-up, involvement of the right eye was identified very late. The patient's evolution is analyzed, as well as the causes that prevented early detection of traumatic optic neuropathy in the right eye. CONCLUSIONS Functional evaluation must be used to search for traumatic optic neuropathy in every injured eye. The absence of ocular fundus abnormalities does not rule out the disease, especially when visual deficiency exists. Detection of patients with a positive pupil during initial evaluation of trauma is required in order to refer the patient in a timely manner to the ophthalmologist. The specialist should identify atypical cases and therapy should be initiated as early as possible.